/*
 * Copyright 2012-2018 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package cn.springcloud.gray.bean.properties.source;

import cn.springcloud.gray.bean.origin.Origin;
import cn.springcloud.gray.bean.origin.OriginProvider;
import cn.springcloud.gray.bean.origin.OriginTrackedValue;
import org.springframework.core.style.ToStringCreator;
import org.springframework.util.Assert;
import org.springframework.util.ObjectUtils;

/**
 * A single configuration property obtained from a {@link ConfigurationPropertySource}
 * consisting of a {@link #getName() name}, {@link #getValue() value} and optional
 * {@link #getOrigin() origin}.
 *
 * @author Phillip Webb
 * @author Madhura Bhave
 * @since 2.0.0
 */
public final class ConfigurationProperty
        implements OriginProvider, Comparable<ConfigurationProperty> {

    private final ConfigurationPropertyName name;

    private final Object value;
    private final Origin origin;


    public ConfigurationProperty(ConfigurationPropertyName name, Object value,
                                 Origin origin) {
        Assert.notNull(name, "Name must not be null");
        Assert.notNull(value, "Value must not be null");
        this.name = name;
        this.value = value;
        this.origin = origin;
    }

    public ConfigurationPropertyName getName() {
        return this.name;
    }

    public Object getValue() {
        return this.value;
    }

    @Override
    public Origin getOrigin() {
        return this.origin;
    }

    @Override
    public boolean equals(Object obj) {
        if (this == obj) {
            return true;
        }
        if (obj == null || getClass() != obj.getClass()) {
            return false;
        }
        ConfigurationProperty other = (ConfigurationProperty) obj;
        boolean result = true;
        result = result && ObjectUtils.nullSafeEquals(this.name, other.name);
        result = result && ObjectUtils.nullSafeEquals(this.value, other.value);
        return result;
    }

    @Override
    public int hashCode() {
        int result = ObjectUtils.nullSafeHashCode(this.name);
        result = 31 * result + ObjectUtils.nullSafeHashCode(this.value);
        return result;
    }

    @Override
    public String toString() {
        return new ToStringCreator(this).append("name", this.name)
                .append("value", this.value).append("origin", this.origin).toString();
    }

    @Override
    public int compareTo(ConfigurationProperty other) {
        return this.name.compareTo(other.name);
    }

    static ConfigurationProperty of(ConfigurationPropertyName name,
                                    OriginTrackedValue value) {
        if (value == null) {
            return null;
        }
        return new ConfigurationProperty(name, value.getValue(), value.getOrigin());
    }

    static ConfigurationProperty of(ConfigurationPropertyName name, Object value,
                                    Origin origin) {
        if (value == null) {
            return null;
        }
        return new ConfigurationProperty(name, value, origin);
    }

}
